Priming of internal-combustion engines



Nov. 1 2, 1946.

A. E. MQREILLON ET AL 2,411,103 PRIMING OF INTERNAL-COMBUSTION ENGINES Filed Feb. 15, 1945 2 Sheets-Sheet 1 k INv ENTQRS 63 A .E. MORE LLQN J. l vHUNT A TYS.

1945- A. E. MOREILLON ET AL 2,411,103

PRIMING OF INTERNAL-COMBUSTION ENGINES Filed Feb. 15, 1945. Z 'Sheet -Sheet 2" 1 6/ Fig.2

11% v elm/ og s Patented Nov. 12, 1946 PRIMING F INTERNAL-COMBUSTION ENGINES Albert Edmund Moreillon and Joseph Anthony Hunt, Redditch, England, assignors to The Heywood Compressor Company Limited, Redditch, England, a British company Application February 15, 1945, Serial No. 578,098

In Great Britain September 1, 1944 turn stroke at each operation and cannot be caused to commence a second delivery stroke until the return stroke is completed.

The invention further consists in a priming system for an internal combustion engine comprising a pneumatically operated piston type fuel pump with a spring return or suction stroke, with the piston coupled to the compressed air exhaust valve in combination with a snap action mechanism for such valve, so that the valve is opened only at the end of the piston delivery stroke and closed only at the end of the piston suction stroke.

The invention further consists in a priming system for an internal combustion engine, in which the exhaust valve is held closed by the compressed air and the snap action mechanism, opened by the piston through a lost motion connection at the end of its delivery stroke and closed by the piston which overcomes the snap action mechanism at the end of the suction stroke.

The invention further consists in a priming system for an internal combustion engine, having a push button operated compressed air valve for delivering compressed air to the priming pump to effect the delivery stroke of the latter, the suction stroke being effected by spring pressure, a piston ,operatively connected to the compressed air valve retaining such valve open so long as air pressure is maintained in the delivery connection from valve to pump, the latter being operatively connected to the compressed air exhaust valve.

In the accompanying drawings:

Figure 1 is a diagram of an engine priming system arranged in one convenient form in accordance with this invention.

Figure 2 is a sectional view of the priming pump and its control device shown in Figure 1.

The piston a of the priming pump is loaded by the spring I) in the petrol cylinder 0 which has a petrol inlet valve at d and a petrol outlet valve at e,

Compressed air is admitted at f to force the piston a upwards to effect delivery. Such compressed air also holds the atmospheric or exhaust valve g on its seat. The valve 9 is loaded by a spring it within a bobbin i which has an annular rib 9' therearound which cooperates with a spring loaded ball I; to constitute a snap device to hold the bobbin down on the valve g or to hold it raised with the valve liftedclear of its seat. The stem m of the valve g has a cross pin 11. therein which when the bobbin i is raised is engaged by the bobbin in order to lift the valve g off its seat. There is a stem 0 secured to the top of the bobbin 2' and this stem projects through the piston a into the space p where the stem has a nut or collar q adjustably secured thereon.

When the piston a is forced upwards by compressed air in the space 1* in order to effect petrol delivery, the valve g is held on to its seat by the air pressure until the internal shoulder s in the piston abuts against the collar q on the stem 0, when the piston raises the stem 0, which in turn raises the bobbin 2' and the stem m of the valve 9. The latter is therefore opened and the compressed air allowed to escape to exhaust. The spring I) now depresses the piston or which draws petrol into the cylinder 0 past the inlet valve 11. As the piston approaches the end of its suction stroke, it presses on the shoulder u of the stem 0 and forces the bobbin 1' downwards to close the valve 9. When the bobbin 2' is raised, the rib depresses the ball k which then snaps back on the opposite side of the rib. When the bobbin is lowered, a reverse action takes place and the ball returns to the position shown in the figure where the bobbin is held down on to the valve g. ihe

valve 9 is therefore opened only when the pump a completes its delivery stroke and closed when the pump completes its suction stroke.

The control of the flow of compressed air to the pump inlet 7 is effected by a valve 11 loaded by a spring w and pushed off its seat by a stem an attached to a piston y which is held in its raised position by a spring .2 and is depressed by a push button 2 and stem 3. The air inlet to the valve fitting is at 4. When the valve '0 is open, air passes not only to the outlet pipe 5 but also by Way of the passage 6 to the top of the piston "I, so that such piston is held in the depressed pojsition to which it is moved by the push button 2 so long as there is compressed air in the pipe 5, that is so long as the piston a of the petrol pump is on its delivery stroke. Immediately the valve 9 is opened and the air pressure released, the spring a raises the piston y and with it the stem :1: so that the valve 1; is allowed to close.

3 It follows therefore that once the push button 2 has been depressed, the valve 2; is held open by the piston y until the pump piston a has completed its delivery stroke and opened the exhaust valve g. j

The delivery from the pump valve e is to priming sprayers or injectors 8 in the engine induction manifold 9, and in Figure 1, l 0 indicates the priming fuel supply tank, and H a compressed air supply vessel.

With our improvement, the operator or pilot will give as many effective pushes to his push button as he requires strokes of petrol tobe injected for priming purposes and he cannot give half or partial strokes to his priming pump.

What we claim is:

1. A priming system for an internal combustion engine comprising a pneumatically operated fuel pump with a spring return for the suction stroke, and a control device so arranged that the pump must perform one complete delivery and 'return stroke at each operation and cannot be caused to commence a second delivery stroke until the returnstroke is completed.

2. A priming system for an internal combustion engine comprising a pneumatically operated piston type fuel pump with a spring return for the suction stroke, with the piston coupled to a compressed air exhaust valve in combination with a snap action mechanism for such valve,

so that the valve is opened only at the end of the piston delivery stroke-and closed only at the end of the piston suction stroke. Y

3. A priming system for an internal combustion engine as claimed in claim 2, in which the exhaust valve is held closed by the compressed air and the snap action mechanism, opened by the piston through a lost motion connection at the end of its delivery stroke and closed by the piston which overcomes the snap action mecha-- nism at the end of the suction stroke.

4. In a priming system for an internal combustion engine according to claim 2, a push button operated compressed air valve for delivering compressed air to said fuel pump to efiect the delivery stroke of the latter, the suction stroke being effected by spring pressure in said pump. a piston operatively connected to the compressed air valve retaining such valve open so long as air ,pressure is maintained in the delivery connection from valve to pump, the latter being operatively 25 connected to said compressed air exhaust valve.

ALBERT EDMUND MOREILLON. JOSEPH ANTHONY HUNT. 

